Kartikaya Gupta (email:kats@mozilla.staktrace.com) Assignee
	Description • 11 years ago

Right now APZCTreeManager is using the mViewport field from the FrameMetrics for hit testing. This sort of works most of the time, but there have definitely been occasions where it is not correct, and trying to scroll a subframe resulted in the parent frame scrolling and vice-versa.

Based on the documentation in FrameMetrics.h, mViewport is supposed to be the CSS viewport for the frame, which in the case of subframes may be different from the desired hit test region (if the subframe has a meta-viewport tag). Instead, we should switch over to using the mCompositionBounds which more accurately corresponds to the hit test region, once botond lands the patch in bug 904533.

	Kartikaya Gupta (email:kats@mozilla.staktrace.com) Assignee
	Comment 1 • 11 years ago

Possible patch

	Botond Ballo [:botond]
	Comment 2 • 11 years ago

Comment on attachment 800199 [details] [diff] [review]
Patch

Review of attachment 800199 [details] [diff] [review]:
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Together with my patch for bug 912806, this patch fixes the issue I was seeing where hit testing results were wrong in a zoomed-in state.

	Kartikaya Gupta (email:kats@mozilla.staktrace.com) Assignee
	Comment 3 • 11 years ago

I also updated the layer border to reflect the composition bounds; it looks like that's meant to be in sync with the hit test area.

	Kartikaya Gupta (email:kats@mozilla.staktrace.com) Assignee
	Comment 4 • 11 years ago

https://hg.mozilla.org/integration/b2g-inbound/rev/988953e0c208

	Ryan VanderMeulen [:RyanVM]
	Comment 5 • 11 years ago

https://hg.mozilla.org/mozilla-central/rev/988953e0c208